Caudalie's Resveratrol Lift Instant Firming Serum Refill (30ml) is a concentrated treatment with a lightweight texture that sits seamlessly beneath make up. Resveratrol (a skin-smoothing staple derived from grapevine stalks, by the way) is the star ingredient in this serum, working to smooth, firm and plump the skin's appearance for a radiant-looking complexion. That's not all, either; a helping of peptides, mahogany bark collagen and quenching hyaluronic acid grant hydration and protect the skin's natural moisture barrier. The cherry on top? The handy refill means you never have to be without your favourite skin care again.